Cecilia Hammenhag, associate professor at the Swedish University of Agricultural Sciences (SLU), Alnarp, is responsible for this project, part of SLU Grogrund. She is holding a glass bottle with a clip top, which contains peas of many different colours and sizes. The peas in the bottle are just a fraction of the 300 varieties that have arrived from around the globe. They have been selected to withstand climate conditions that are increasingly frequent: long periods of drought with high rainfall in between.

...selected to withstand climate conditions that are increasingly frequent: long periods of drought with high rainfall in between.

“Plants have different strategies for coping with this type of climate,” says Hammenhag. “They either have a big root system that helps them go deep into the ground to find water, or they are good at conserving water. Heavy rainfall means that plant tissues, like their roots, suffocate when they are under water – plants that can cope with this can quickly and effectively replace damaged root tissue. In this research project, we have found varieties that can withstand both drought and lots of water in experimental conditions.” The 300 varieties that have been collected range from wild varieties to landraces (unimproved varieties genetically adapted to the environment in which they grow) and peas that were the result of breeding programmes. All the pea varieties were examined in an analyser that scans the peas and provides detailed data about their seed characteristics. The colour and pattern of the pea pods are also studied, because these properties may be linked to the nutritional content of the seed. A wrinkly pea
has a lower starch content. A pea that will be eaten must also be cookable.

A pea that will be eaten must also be cookable.

Some peas may have qualities that can be transferred to new varieties, but so far which ones could be useful is unknown. “The food industry wants varieties with a high protein content and stable qualities that do not vary from year to year,” says Hammenhag. The next step will be investigating how to reduce the levels of bitter saponins. These are potentially toxic substances that defend the plant. Peas contain this substance, which can cause problems when protein is extracted. Naturally, it is important for the plant, as it protects it from pests and infestations. Of course, the best thing would be if we could produce an ingredient that tasted of nothing. “We have to balance reducing the bitter substances while maintaining the plant’s defences, she concludes.”

Text: Ingar Nilsson
Photo: Rebecca Gustafsson